Optical imaging systems such as optical coherence tomography (OCT) systems generate images or measurements by measuring the intensity of light backscattered or backreflected from a specimen and providing a gray scale or false color two-dimensional representation of this light intensity in a plane or cross-section through the object image being measured. OCT enables the non-excisional, in situ, real-time imaging of microstructure of a specimen with a resolution of approximately 2-20 microns.
An OCT system can be separated into an imaging engine and probes. The imaging engine contains the optical light source, optical interferometer and other optical detection elements, as well as electronics, motor, control(s), and computers for image generation and display. The probes are modules which are attached to the engine and direct light to and from the specimen that is to be measured or imaged.
In spite of advances in probe construction and in related delivery and scanning techniques, existing probes are not suitable for examination of tissues within lumens with a wide range of diameters. Some regions of the gastrointestinal system, such as the esophagus and duodenum, may have a diameter of 18 mm or more. Although the diameters of these structures are relatively large, the probes that fit within existing endoscopes and catheters used to examine them, are comparatively small in diameter to fit within endoscopic channels. The present invention aims to overcome these limitations.